2 * Driver for EHCI UHP on Atmel chips
4 * Copyright (C) 2009 Atmel Corporation,
5 * Nicolas Ferre <nicolas.ferre@atmel.com>
7 * Based on various ehci-*.c drivers
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file COPYING in the main directory of this archive for
14 #include <linux/clk.h>
15 #include <linux/dma-mapping.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
20 #include <linux/of_platform.h>
21 #include <linux/platform_device.h>
22 #include <linux/usb.h>
23 #include <linux/usb/hcd.h>
27 #define DRIVER_DESC "EHCI Atmel driver"
29 static const char hcd_name[] = "ehci-atmel";
30 static struct hc_driver __read_mostly ehci_atmel_hc_driver;
32 /* interface and function clocks */
33 static struct clk *iclk, *fclk, *uclk;
36 /*-------------------------------------------------------------------------*/
38 static void atmel_start_clock(void)
40 if (IS_ENABLED(CONFIG_COMMON_CLK)) {
41 clk_set_rate(uclk, 48000000);
42 clk_prepare_enable(uclk);
44 clk_prepare_enable(iclk);
45 clk_prepare_enable(fclk);
49 static void atmel_stop_clock(void)
51 clk_disable_unprepare(fclk);
52 clk_disable_unprepare(iclk);
53 if (IS_ENABLED(CONFIG_COMMON_CLK))
54 clk_disable_unprepare(uclk);
58 static void atmel_start_ehci(struct platform_device *pdev)
60 dev_dbg(&pdev->dev, "start\n");
64 static void atmel_stop_ehci(struct platform_device *pdev)
66 dev_dbg(&pdev->dev, "stop\n");
70 /*-------------------------------------------------------------------------*/
72 static int ehci_atmel_drv_probe(struct platform_device *pdev)
75 const struct hc_driver *driver = &ehci_atmel_hc_driver;
77 struct ehci_hcd *ehci;
84 pr_debug("Initializing Atmel-SoC USB Host Controller\n");
86 irq = platform_get_irq(pdev, 0);
89 "Found HC with no IRQ. Check %s setup!\n",
90 dev_name(&pdev->dev));
95 /* Right now device-tree probed devices don't get dma_mask set.
96 * Since shared usb code relies on it, set it here for now.
97 * Once we have dma capability bindings this can go away.
99 retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
101 goto fail_create_hcd;
103 hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
106 goto fail_create_hcd;
109 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
110 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
111 if (IS_ERR(hcd->regs)) {
112 retval = PTR_ERR(hcd->regs);
113 goto fail_request_resource;
116 hcd->rsrc_start = res->start;
117 hcd->rsrc_len = resource_size(res);
119 iclk = devm_clk_get(&pdev->dev, "ehci_clk");
121 dev_err(&pdev->dev, "Error getting interface clock\n");
123 goto fail_request_resource;
125 fclk = devm_clk_get(&pdev->dev, "uhpck");
127 dev_err(&pdev->dev, "Error getting function clock\n");
129 goto fail_request_resource;
131 if (IS_ENABLED(CONFIG_COMMON_CLK)) {
132 uclk = devm_clk_get(&pdev->dev, "usb_clk");
134 dev_err(&pdev->dev, "failed to get uclk\n");
135 retval = PTR_ERR(uclk);
136 goto fail_request_resource;
140 ehci = hcd_to_ehci(hcd);
141 /* registers start at offset 0x0 */
142 ehci->caps = hcd->regs;
144 atmel_start_ehci(pdev);
146 retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
149 device_wakeup_enable(hcd->self.controller);
154 atmel_stop_ehci(pdev);
155 fail_request_resource:
158 dev_err(&pdev->dev, "init %s fail, %d\n",
159 dev_name(&pdev->dev), retval);
164 static int ehci_atmel_drv_remove(struct platform_device *pdev)
166 struct usb_hcd *hcd = platform_get_drvdata(pdev);
171 atmel_stop_ehci(pdev);
178 static const struct of_device_id atmel_ehci_dt_ids[] = {
179 { .compatible = "atmel,at91sam9g45-ehci" },
183 MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
186 static struct platform_driver ehci_atmel_driver = {
187 .probe = ehci_atmel_drv_probe,
188 .remove = ehci_atmel_drv_remove,
189 .shutdown = usb_hcd_platform_shutdown,
191 .name = "atmel-ehci",
192 .of_match_table = of_match_ptr(atmel_ehci_dt_ids),
196 static int __init ehci_atmel_init(void)
201 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
202 ehci_init_driver(&ehci_atmel_hc_driver, NULL);
203 return platform_driver_register(&ehci_atmel_driver);
205 module_init(ehci_atmel_init);
207 static void __exit ehci_atmel_cleanup(void)
209 platform_driver_unregister(&ehci_atmel_driver);
211 module_exit(ehci_atmel_cleanup);
213 MODULE_DESCRIPTION(DRIVER_DESC);
214 MODULE_ALIAS("platform:atmel-ehci");
215 MODULE_AUTHOR("Nicolas Ferre");
216 MODULE_LICENSE("GPL");